Electric switch



Dec. 30, 1930. WQQ Df ELECTRIC SWITCH Filed Nov. 3, 1924 I 2 shgets-sheet 1 ,Tnvenior.

J. D. woob Dec. 30,

ELECTRIC swITG Filed Nov. 3, 1924 2' Sheet's -Sheet 2 Patented Dec. 30, 1930 JOSEPH D. WOOD, OF QUINCY, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS,

'TO CONDIT ELECTRICAL MANUFACTURING CORIORATION, OF BOSTON; MASSACHU- SETTS, A CORPORATION OF MASSACHUSETTS ELECTRIC SWITCH Application filed November 3, 1924. Serial No. 747,478.

paratus and, specifically for an oil-immersed electric switch, with means to catch the oil or equivalent fluid expelled from the casing, and cool the hot gases and vapors before they escape into the atmosphere whereby'to reduce the fire hazard.

A further object is generally to improve the construction and operation of electric switches.

Fig. 1 is a side elevation partly in section, of an electric switch embodying" the invention.

Fig. 2 is a plan view of the oil receptacle and associated gas-cooling means removed from the switch.

Fig. 3 is a transverse sectional elevation of the switch casing of Fig. 1, the switch members and operating mechanism being removed.

Fig. at is a perspective detail of the switch 12 which surrounds the inner receptacle and is adapted to catch oil vented into it from the inner receptacle. Said receptacles may be supported on a wheeled platform 14. A switch frame 16 may be supported by standards 1.8 in elevated position from and above said platform 14 and may comprise a cover for said inner receptacle. Stationary switch members 20 may be carried by said switch frame and depend therebelow into the oil contained in said inner receptacle; and a movable switch. or bridging member 22 may cooperate with said stationary switch members to control the circuit through the switch. Operating mechanism 24 may be contained within and be supported by said casing and arranged to actuate said movable switch-member. Said switch frame may be formed or provided with two approximately parallel and annular flanges 9.6 and 28 at the lower edge thereof, which flanges are spaced apart to provide a continuous annular groove 30 adapted to con.

' form with and receive the upper edge of the inner oil receptacle 10. A packing 32 may be disposed in said groove and the upper edge of said oil receptacle is adapted to seat on said packing whereby to form an approximately gas tight joint thereat. The outer receptacle 12 is adapted to be disposed about and rise somewhat above said outer flange 28 and be spaced laterally therefrom; and gases are adapted finally to be vented from the switch through the space between said flange and said outer receptacle.

The gases and vapors generated within the inner oil receptacle during circuit-interrupt on are adapted to use into the 1nter1or of the switchframe, which forms an exp'an sion space for the gases and vapors, and then be directed into the space between the two rcceptacles' wherein means are provided to cool the hot gases and condense the vapors. To this end, said switch frame is formed or provided' with similar gas passages 34 approXimately vertically disposed in each end of the casing and isolated from the interior of the casing, except at the upper ends, by the end walls 36 of the switch-frame. Cover plates 38 are secured ren'iovably to the end-walls of the switch frame and in spaced relation therewith, to form enclosing walls for said passageu. Said venting passages 3-il are in communication with the interior of the switch frame at their upper ends, by means of the openings or entrances 40, and baffiewalls 42 are disposed beneath. said openings and are extended more or les horizontally into the interior of the switch frame for the purpose of deflecting upwardly-inoving mass-cs of oil away from the entrances of the passages. Depending battle-walls ll may be disposed in front of said openings 40, and walls 42, in spaced relation therewith, for

' the same purpose. As thus arranged, the hotgases and vapors pass from the top of the gas expansion space within the switch frame into said end-passages 3d and down said passages into the space between the end walls of the two receptacles. The cover plates 38 are adapted to extend for a substantial distance into the space between said receptacles and be disposed snugly in contact with the end walls of the outer receptacle to form an approximately gas tight contact therewith.

Means are disposed between the end walls of the two receptacles and beneath the exit openings 34a of said gas passages 3% to cool the hot gases and condense the hot vapors. Said means may comprise a plurality of vertically-disposed plates l6, which plates are extended laterally across the outer receptacle and across the spaces included between the side walls of the receptacles whereby approximately to isolate the end and side spaces and direct the gases to flow downwardly between the plates. Said plates are of substantial length and may be supported in position above the bottom of the outer receptacle in any suitable manner as by resting upon the brackets 48, which brackets may be disposed. between the end walls of the receptacles and secured thereto. Said plates are adapted to be supported in relatively closely spaced relation whereby to provide relatively narrow passages down which the heated gases are adapted to flow.

Due to the relatively line sub-division of the gas stream, practically all portions of it are acted upon by the cold plates and consequently the is cooled so that there is but little danger of flame being thrown from the switch; and the vapors are cooled and con densed and the condensate collects in the bottom of the outer receptacle below the lower eilges of said plates. lVhile the-individual passages between the plates may be relatively narrow, the aggregate number of passages is relatively large so that a relatively large total venting area is provided between the plates.

The plates may be supported in spaced relation in any suitable manner as, for instance, by corrugating the pl.ate-supporting brackcts to provide recesses 49, Fig. 6, in which the lower edges of the plates are received.

The cooled gas stream, composed mainly of cool uncondensible gases, passes from the lower edges of the cooling plates and flows laterally under the lower edges of said plates into the side spaces between the two receptacles, the space between the receptacles at the sides and ends being in free communica tion, and thence passes upwardly and escapes from the opposite sides of the switch out of the open top of the outer receptacle.

The switch-frame is formed or provided with extensions 52 on the opposite sides and adjacent the ends thereof, which extensions are adapted to extend into the side spaces between the two receptacles and prevent the passage of any appreciable amount of hot from the spaces above the tops of the cooling plates directly out of the switch. For the same purpose lugs 54: may depend from said extensions into the space between the two receptacles and lie against said plates.

The structure may be otherwise modified without departing from the spirit of the invention.

I claim:

1. An electric switch having an outer oilcatching receptacle, an oil-containing receptacle disposed within and having its side walls spaced from the side walls of said outer re ceptacle, separable switch members located in the oil in said oil-containing receptacle, a plurality of relatively closely-spaced metal plates having approximately parallel surfaces disposed in the upper portion of the space between said two receptacles, and means to direct fluid from said inner receptacle to flow downwardly between said plates and into said outer receptacle.

2. An electric switch having an outer spill receptacle, an oil-containing receptacle disposed within and spaced from the side walls of said outer receptacle and arranged to enclose the current carrying components of the switch, and a conduit for gaseous fluid having restricted lateral dimensions arranged in communication with the upper portion of said inner receptacle and extended downwardly in said outer receptacle in a portion only of the lateral extent of the space between said two receptacles and terminated above the bottom thereof, the space in said spill receptacle below said conduit adapted to hold oil expelled through said conduit from said inner receptacle.

3. An electric switch having an outer receptacle, an oil-containing receptacle disposed within and spaced from the side wall of said outer receptacle, and two opposed conduits forgaseous fluid arranged in-independent communication with the upper portion ion of said inner receptacle and extended down wardly in said outer receptacle in opposed .iortions thereof and terminated above the ottoni thereof and having independent communication with said outer receptacle, said outer receptacle havlng means to vent to the atmosphere between said conduits.

4. An electric switch having an'out-er oil free receptacle, an oil-containing receptacle disposed within and spaced from the side walls of said outer receptacle, a normally oil .free conduit for gaseous fluid arranged in communication with the upper portion of said inner receptacle and extended downwardly in said outer receptacle and terminated above the bottom thereof, and a plurality of relatively closely-spaced gas-cooling plates disposed in said conduit.

5. An electric switch having an outer receptacle, an oil-containing receptacle disposed within and spaced from the side walls of said outer receptacle, and two opposed conduits for gaseous fluid arranged in communication with the upper portion of said inner receptacle and extended downwardly in said outer receptacle in opposed portions thereof and terminated above the bottom thereof, said outer receptacle having means to vent to the atmosphere between said conduits, and a plurality of relatively closely-' spaced gas-cooling plates disposed in said conduits.

6. An electric switch having a rectangu lar outer receptacle, a rectangular oil-con-. taining receptacle disposed within and spaced from the side and end walls of said outer receptacle, means to isolate the space.

between two proximate end walls of said receptacles from the space between the side walls thereof for a major portion of the height of said walls, whereby to provide a gas conduit, a plurality of relatively closely spaced metal plates approximately vertically-disposed in said conduit, and means to direct gaseous fluid to pass from the upper portion of said inner receptacle into the upper portion of said conduit and down wardly between said plates.

7. An electric switch having a casing including an oil receptacle, and a switch frame disposed above and comprising a cover for said receptacle, said frame having an annular flange which surrounds and depends below the top of said receptacle, and also having a downwardly-extended venting conduit which overlies said flange and is arranged in communication with the interior of the casing at the upper portion thereof above the oil and is terminated adjacent the bottom of said switch frame, said flange comprising an inner wall of said conduit.

7 8. An electric switch having a casing in cluding an oil receptacle, and a switch frame disposed above and comprising a cover for said receptacle, said frame having an ,annuing a downwardly-extended venting conduit which overlies said flange andis arranged in communication with the interior of the casing at the upper portion thereof above the oil and is terminated adjacent the bottom of said switch frame,saidflange forming an inner wall of said conduit, and a recep tacle disposed beneath said conduit and surrounding said oil receptacle.

9. An electric switch having a casing including an oil receptacle, and a switch frame disposed above and comprising a cover for said receptacle, said frame having an annular flange which surrounds and depends below the top of said receptacle, and also having a downwardly-extended venting conduit arranged in communication with the interior of the casing at the upper portion thereof andterminated adjacent the bottom of said switch frame, a second receptacle disposed beneath said conduit and surrounding said oil receptacle, and a plurality of closelyspaced metal plates disposed in said second receptacle below and in the path of the gas stream from said conduit.

10. An electric switch having a casing including an oil receptacle and a switch frame disposed above and comprising a cover for said receptacle, said switch frame having a downwardly-directed vent passage in its side walls which is provided with an entrance to the interior of the casing immediately beneath the top of the switch frame, and an approximately horizontally-disposed baffle disposed immediately beneath said entrance and extended for a substantial distance into the interior of the casing. 11. An electric switch having a casing including an oil receptacle and a switch frame disposed above and comprising a cover for said receptacle, said switch frame'having a downwardly directed vent passage in its side walls which is provided with an entrance to the interior of the casing immediately beneath the top of the switch frame, an approximately horiZontally-disposed bafile disposed immediately beneath said entrance and extended for a substantial distance into the interior of the casing and a baffle-plate depending from the top of said switch frame and disposed in spaced relation in front of said entrance and first baffle plate.

12. In an oil-immersed electric switch, an oil receptacle and a switchvcasing comprising a cover therefor, said cover having depending inner and outer side walls which overlie the oil receptacle and a downwardlyextended conduit enclosed in said side walls and open at the bottom and in communication with the interior of the cover only at the top thereof.

13. In an oil-immersed electric switch, an enclosing casing including a switch frame comprising a cover for the casing, said cover having WELHS which define a vent-conduit which extends downwardly at the side of the casing and is open at the bottom and is in communication With the interior of the casing only at the top thereof through said cover.

In testimony whereof, I have signed my name to this specification.

JOSEPH D. WOOD. 

